By Ellen Dannin

Next year, when the Pennsylvania Turnpike Commission again holds public meetings about the future of Interstate 80, we must demand answers to hard questions that so far have gone unasked.

One of the biggest questions is how we get from revenue predictions to real revenues. Since the tolls are to fund mass transit and highway and bridge projects around the state, it is essential that this question be answered.

Tolls do not magically appear. Before the first toll can be collected, collection infrastructure must be installed, and this will be expensive.

Electronic tolling, through e-passes, cannot solve the problem. In the summer, Illinois and Indiana were embroiled in an e-pass border war that turned freeways into parking lots over incompatible systems.

More fundamentally, a toll road cannot succeed if only e-pass drivers can use the road. There must be collection kiosks that accommodate both those with electronic passes and those who use cash.

Collection points slow traffic. So, since what highways sell is speed, toll roads are built with limited entries and exits. Interstate 80 was not built as a toll road, so its many exits and entrances will be choke points for toll collection. Closing entrances would drive motorists - and revenue - away, so there must be collection points at each entrance. It's all or nothing.

One high-tech solution is shadow tolling. Under shadow tolling, traffic is measured, and the owner or lessor of the toll road bills the government in lieu of toll collections. Unfortunately, shadow tolling relies on a level of technology to count traffic that we do not yet have. Until it is trustworthy, it will be vulnerable to over- or understating the level of traffic. Worse, the plan for I-80 is not to have the state pay a private operator but to lease the interstate to generate additional revenue. Thus, shadow tolling is not a useful solution. The only answer is toll collection at every entrance and exit.

Entrances and exits for I-81 were not designed to house lanes for electronic and cash toll collection. People with electronic passes will not want to wait in line behind someone who does not. Additional lanes will have to be built and built quickly.

The solution seems to be to use the "design-build" method to speed construction. When one entity is both the designer and the builder, the builder is already up to speed on the construction details.

However, design-build amplifies opportunities for corruption that already exist in highway construction, because it shrinks the number of checks on the process. It gives more power to the designer, those making the financial projections and preparing the contracts and paperwork, and builders - all of whom will be paid and gone by the time problems surface.

Three years after Colorado's limited-access toll road, the E-470, was opened in 1991, investors and the public learned that projected revenues had been knowingly inflated by 25 percent. No one blew the whistle. If the public's interests are to be protected, there must be someone whose interests are not aligned with the designers, builders, and finance consultants. There must be someone with the expertise, courage and power to spot bad decisions, tell the truth, and put the brakes on.

Pennsylvanians should be worried by Notre Dame University professor Roger Skurski's 2006 study that found the $3.85 billion Indiana Toll Road lease should have been closer to $11.38 billion.

We need to ask whether privatizing the I-80 deal includes a hidden price, as was the case with the Northwest Parkway around Denver. When its terms were revealed, the public learned that the lease included a noncompete agreement that guaranteed income to the private investors by punishing communities that improved their roads or built or improved mass transit systems.

If the Pennsylvania Department of Transportation and the Turnpike Commission have reason to expect better outcomes, they must lay out their reasons for optimism. We Pennsylvanians have a lot riding on a good system of roads and bridges. Whether we personally use I-80 or the turnpike, these roads are the way we bring goods we need into the state and export our products.

The public deserves information about how we get from revenue predictions to actual revenue. But so far, the state has been unwilling to provide it.

Ellen Dannin is a professor of law at Pennsylvania State University's Dickinson School of Law.